Some attachments fail to download when using the file attachment macro

Summary

When attempting to download an attachment from a page using the file attachment macro, the attachment fails to download

Environment

Cloud 1000.230.0

Expected Results

Attachment should download

Actual Results

Attachment does not download
Confluence displays a 'Page cannot be found' page

An error like the following can be seen in the Developer console of the web browser:

/wiki/download/attachments/65146700/20070711_filename?api=v2

Notes

The files appear to be in the file system as they are represented as a '1' which is present
When attempting to preview one of these attachments, the preview is displayed without any error

Workaround

If the issue is with a Word doc, it appears that you can expand the attachment information panel
Click the 'Edit in Office' button
Save a new version of the attachment